Occasionally a phone number will return an error message to our text club provider indicating that the subscriber's profile is blocked. This translates to the customer not having messaging to and from shortcodes (like 21333) enabled on their phone.
This is a separate setting from texting in general, because this customer will still be able to text friends, just not the shortcode. This is something that some cell phone users opt to turn off in order to not receive marketing messages or to bar children from texting in to premium campaigns that add money onto the monthly bill (usually ringtone / game / wallpaper oriented).
In order to receive messages from our SK Text Club, please contact your service provider to change the account settings to enable messages to and from shortcodes. We look forward to your participation in the SK Text Club!